I have no idea bro. Stopped using Jio since an year and half. In Mumbai, my experience has been pathetic, no matter which phone you try. Especially calling. Lots of call drop issues and blank coverage areas even though I am in full range. Operator like Jio should not exist in my opinion. Yes, it has brought revolution, but again cap on speeds when your network can offer so much is pathetic. We are paying almost similar( and not half the price) to the competition and give us service we want. Coverage is top notch, but that isn't sufficient. Only problem is peak time speeds in urban areas, otherwise superfine according to me. Can join if I see improvement in 4G speeds after 5G launch(And to be honest I don't even need speeds over 100Mbps). Till then happy with Vodafone. Everywhere available where I go and most importantly it works even in jungle. Vodafone giving superb service here in Mumbai. Call quality has improved since March 2021 both in Mumbai and Pune(These two cities I will be in most of the times for next five years). And I am happy with it.
According to the start and stop frequency of 700Mhz band, B28b type is used. So rip those B28a phones (especially redmi k50i), it won't work in this frequency.